How would you guys act if you got a letter from a girl saying that every time she sees you, you brighten her day, you would know from that, that she likes you right?

And if this guy said hi to you at one time, and after that the both of you started talking as friends you could say, and after a while he acted weird as if he didn't want to talk to you anymore, and you decided to give him a little of his own medicine which is to ignore him. Would that make you ignore her even more as well, and not even say hi anymore? If he doesn't say hi to you anymore does this mean that he's just not interested in you or could it be because at one time she sort of like ignored you?

How do you think I can get him to talk to me again? Do I still have a shot? I would really appreciate your responses.